Along with these captions, the actor shared a series of photos related to the hit SBS drama, in which they all starred last year, alongside actress Gong Hyo Jin.

In one of the pictures, Lee Kwang Soo, Jo In Sung, and D.O can be seen posing closely together, as they wrap their arms around each other. D.O sits in the middle and is holding a small cake with one candle, signifying their one-year anniversary. In another picture, Jo In Sung and Lee Kwang Soo take on a cute pose.